AngularJS vs Angular: Key Differences Explained

Briefly: AngularJS vs Angular

Main Differences

Programming Language

• AngularJS: written and uses JavaScript.
• Angular: based on TypeScript (JavaScript extension with types).

TypeScript makes code more predictable, self-documenting and easily maintainable.

Architecture

• AngularJS uses MVC/MVVM: controllers, templates and $scope.
• Angular is built on components and modules — each UI block is isolated, reusable and scalable.

Tooling and Build

• In AngularJS there's no built-in build system — everything needs to be configured manually.
• In Angular there's powerful CLI for generating components, services, tests and running build (ng build, ng generate, ng serve).

Performance

• AngularJS uses two-way data binding and dirty checking, which can slow down large applications.
• Angular uses unidirectional data flow + ChangeDetectionStrategy, which significantly speeds up rendering.

DI (Dependency Injection)

• AngularJS supports DI, but not as flexibly.
• Angular has powerful DI system at class, module and component levels.

Support

• AngularJS is considered deprecated — Google ended official support on December 31, 2021.
• Angular — actively developed, regularly updated (v16, v17 and beyond).

Example: Different Syntax

AngularJS (v1.x)

<div ng-app="app" ng-controller="MainCtrl">
  <p>{{ message }}</p>
</div>

<script>
  angular.module("app", []).controller("MainCtrl", function ($scope) {
    $scope.message = "Hello from AngularJS";
  });
</script>

Angular (v2+)

@Component({
  selector: 'app-root',
  template: `<p>{{ message }}</p>`,
})
export class AppComponent {
  message = 'Hello from Angular';
}